Comparison of ZOTAC GeForce GTX 960 Reference video card vs KFA2 GeForce GTX 1660 video card by specifications and benchmarks. ZOTAC GeForce GTX 960 Reference runs at 1.127 GHz base clock speed and has 2 GB of GDDR5 memory, while video card KFA2 GeForce GTX 1660 runs at 1.530 GHz base clock speed and has 6 GB of GDDR5 memory. The TDP of the first video card is 120 W, and the second is 120 W. Compare the table of benchmark results to find out which graphic card is better.